Spent fuel pools may be configured to provide short-term and/or long-term decay heat removal from irradiated fuel that has been removed from a nuclear reactor. The most recently removed spent fuel may represent the largest source of heat generation in a spent fuel pool. In the event of a complete loss of power to the nuclear power plant or a structural failure of the spent fuel pool containment, cooling systems for the spent fuel pool may not be available to sufficiently remove the fuel's decay heat. For prolonged nuclear plant station blackout conditions, the potential exists to boil off all of the water in the spent fuel pool thereby overheating and subsequently damaging the spent fuel and/or spent fuel cladding.
For the purpose of criticality control, some types of spent fuel storage rack designs may incorporate solid neutron absorbers, such as boron-carbide plates, between each fuel assembly storage position (e.g., cell). The loss of coolant within the spent fuel pool may result in the possibility of rapid zircaloy cladding oxidation or the initiation of a zircaloy fire and subsequent release of radionuclides. Additives such as soluble boron may be provided in a fuel storage pool in order to help maintain subcriticality of spent fuel. Numerous degradation issues to various components may occur over time. Additionally, while the preferential loading of hotter fuel assemblies with colder fuel assemblies may be used to lessen the exchange of heat between adjacent spent fuel assemblies, the effective placement of the fuel assemblies depends on consistent record keeping and is subject to human error. As nuclear reactors may be licensed to continue operating over a period of decades, the spacing and cooling demands on the spent fuel pool are likely to increase with the build-up in spent fuel.
This application addresses these and other problems.